Marian theology (or mariology) is theology that considers Mary in relation to God, to Jesus Christ, and to the Church as a whole. Marian theology is shaped by many things, primarily the Scriptural texts involving Mary, the Marian dogmas of the Church, papal writings relating to Mary, and by the way that Mary is experienced by ordinary Catholics. If you are interested in a sample of Marian theology, a good place to start is with the final chapter of Vatican II’s Dogmatic Constitution on the Church (1964).